Please check your gtranslate/debug.txt file to see which texts it is not able to translate. Search for badRequest.

It seems that one of the characters it tries to translate is "*" (encoded is %2A).

Can you find where in your page you have that character and possible wrap it with <span class="notranslate"></span>.

Also, I can see that you are using a Google Translate API key and probably pay for it. I want to mention that there is no need to pay. You can just remove the API key from the config file and it will work without it.

EDIT: Just checked your source code and was able to find the "*" it is after <input type="text" name="name" id="name" size="40" value="" class="inputbox required" maxlength="50" /> * and some other input tags.